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'Most Important Ever' MySQL Reaches Beta

An anonymous reader writes "The open source database company says it is 'fixing 10 years of critcism in one release', and is aiming at boosting enterprise take-up." Stored procedures. Triggers. Views. It's like it'll be a real DB!

26 of 632 comments (clear)

  1. Information? by Anonymous Coward · · Score: 4, Insightful

    How about linking to an article or page that actually has some useful informtion about what is going to be in the release that makes it "the most important ever"?

  2. Utopia? by rastakid · · Score: 3, Insightful

    The open source database company says it is 'fixing 10 years of critcism in one release'

    If they can fix 10 years of criticiscm in one release, why couldn't do that before? Or maybe in several fixes rolled out within the 10 years?

    1. Re:Utopia? by kpharmer · · Score: 4, Insightful

      > If they can fix 10 years of criticiscm in one release, why couldn't do that before? Or maybe in
      > several fixes rolled out within the 10 years?

      If you recall, their management made the (unconvincing) argument that 99% of the time people didn't need fluff like:
      * referential integrity (pk & fk constraints)
      * views
      * triggers
      * stored procedures

      So, they never implemented this because they had been arguing that nobody needs it anway. Nevermind that it's been standard fare for over twenty years.

      Personally, although I'm glad to see them support views, I would rather have them clean up their exception-handling than add triggers & stored procedures right away. The problems with silent errors, silent truncation of strings & integers, date validation errors, etc are far more serious than what they are adding in this *beta* release.

      Maybe in five years that'll be the release that fixes 15 years of criticism?

  3. Meanwhile, back in 3.23.x land... by polyhue · · Score: 5, Insightful

    A more impressive feat would be to get ISPs who do lots of low-end hosting to actually update from the 3.23.x series for starters... which would probably mean Redhat, Debian, etc. need to ship it. So those users will be seeing this version in... 2008 maybe. 2012. Right after Longhorn comes out.

    1. Re:Meanwhile, back in 3.23.x land... by drspliff · · Score: 5, Insightful

      Thats because a lot of people who 'run web hosting companies' know jack about administration, security and what their users really want, and are just jumping on the internet business bandwaggon.

      It's sad to say, but now with products like Helm, Ensim Webppliance etc. anybody can run a hosting business.

      Anyway, to get to my point (and the end of a rant), because there are a lot of webhosts detatched from 'all that funny dos stuff at the backend' upgrading to newer versions of services etc. can be non-trivial if there isn't a button on their control panel to do it.

      If you have any spare time and want to see for yourself, go traul through the CPanel message boards for threads you'd expect from a unix green-horn, but are actually coming from admins of supposidly 'reliable and respected' hosting companies.

      While it will be a few months into the mysql 5 general release before you start seeing it being used in the hosting industry (I know several people who are just switching over from 4.0 to 4.1), the benifits for developers will be great (in the long run).

      I expect to see a new batch of commercial and open source development spured by the growing stability of mysql 5, but also an increase of help requests from newcomers to web development.

      Btw: I think there should be a new moderator option.. Rant -2

  4. Sounds like troube brewing by instantkarma1 · · Score: 4, Insightful

    Let's see....throwing everything and the kicthen sink into one release can't possibly affect stability, right?

    I love MySQL, and use it, as well as PostgreSQL and Oracle, depending on the project. However, if stability or data integrity becomes an issue because of all these feature additions allowing them to play with the big boys, I'll drop MySQL in a heartbeat.

    If your database isn't reliable, it nothing else really matters.

    1. Re:Sounds like troube brewing by Osty · · Score: 5, Insightful

      the MySQL approach is to add things one at a time, making sure that everything works right from the beginning. It's possible that the endless sniping has caused the MySQL team to abandon its careful development process, but I don't see any evidence of that so far.

      You forgot the most important part: Tell everybody how they don't need a feature, and how they can work around it with application code, and how adding that feature will make MySQL suck to the high heavens, and you really don't want that now, do you? Then, when they finally do add the feature, act like they've never said anything bad about it before. The endless sniping at the MySQL team is completely justified by their cavalier attitude towards proper RDBMS design, and their insistence that the programmer can "easily" work around their incompetent RDBMS design in his application code. If that sniping has encouraged the MySQL to abandon its "careful development process" in favor of turning MySQL into a real RDBMS, then mission accomplished.

  5. Comes with a price by highcon · · Score: 5, Insightful

    And then suddenly, MySQL isn't quite so fast. It used to be, if you need a speedy db and don't need all the fancy features (like integrity) you choose MySQL. If you want to sacrifice a little speed but need features, you got PostgreSQL. Products should stick to what they're good at.

    --
    You can either complain, or do nothing. You don't get both.
  6. Bugfest by Doc+Ruby · · Score: 3, Insightful

    And it will take 10 more years of use to find and address all the bugs in this huge, overdue upgrade. One reason the persistent incremental changes in open-source is better for users, is that we get started on finding and fixing bugs earlier, without a dizzying array of them from which to choose.

    --

    --
    make install -not war

  7. get over it already by jbellis · · Score: 4, Insightful

    if I read "well enough for most purposes" by a mysql fanboy one more time I will have to start drinking before noon.

    popularity isn't proof of clue, guys. How many people run windows, right?

    with postgresql and firebird there have long been available real open-source databases that are just as easy to get up and running as MySQL, but won't hamstring you when you start to learn more.

    I'm glad to see MySQL joining the club, but it must be shocking for the "we don't need no steenkeeng logic in the database" fanboys to adjust... Parent is case in point, I guess.

  8. Re:being a paying customer... by golgotha007 · · Score: 3, Insightful

    I have done enterprise apps and 2 major websites using MySQL.

    The one thing that MySQL excels in is raw speed. It's faster than everything else because it doesn't have all the data integrity features that a RDBMS does.

    However, I stick everything into the application layer, so MySQL lacking these features doesn't bother me a bit.

    As for data integrity; I haven't done a banking application yet, so I'm unconcerned.
    Scheduled DB backups and logging in the application layer keeps me from needing any transaction or rollback features.

    Basically, I'm hoping that the new MySQL won't sacrifice speed for all these features.

  9. NOW IT'S READY FOR THE ENTERPRISE!! by defile · · Score: 5, Insightful

    Copied from my blog^Wweb based journal.

    My retort to a mailing list flamewar over the enterprise readiness of MySQL vs. Oracle vs. PostgreSQL vs. tin cans and string .

    Once you start getting into "serious" work, or "enterprise" level computing, which is all anyone argues about, every single assumption gets tossed out the window.

    Thought your OS was stable? Yeah, it's pretty stable, but when it gets hit all day every day at 100%, it crashes for some reason every few months. I'd love to say that Linux is the exception here, but well, it isn't.

    Maybe you bought the highest quality disks? And avoided the "bad" vendor? Wrong! This year the bad vendor is the one you bought plenty of! Looks like your recovery plan didn't consider that 25% of your disks would fail in the first year!

    Thought you had enough RAM? You don't! And you can't add more because you're on a 32-bit platform. Sucker! Start migrating to 64-bit and learn a whole new bunch of gotchas the hard way.

    Hey! This RAID adapter has an awfully funny glitch! When you pop a brand new disk in, if you reboot, it treats it as a whole new array, and the funniest part is that it renumbers all of the other arrays! Kernel panic: can't mount root device! What a laugh! Good thing we have RAID here to give us added reliability!

    Thought you'd never max out that fridge computer? Well, you just did. It looks like your developers decide to get sloppy when they think they have infinite capacity. A couple of weeks of performance analysis and retuning the algorithms instead of doing real new work!

    Thought that replication setup would scale infinitely? Well, infinitely actually means 10,000 queries/sec. Yup, that's the ceiling. No choice now but to re-architect the whole system into a decentralized dataset. Hey, since it's all so decentralized, lets just store CSV files! Added bonus: management types love it!

    Six months of re-engineering to decentralize the whole system, and another six months to phase it in. And it sure will require downtime!

    For all of the talk of mission critical feature this and enterprise functionality that, in the end, these "real work" loads are handled by the resourcefulness of your people, because no platform is going to even come close to solving all of your problems.

    Package X vs. package Y does not make a difference in the big picture. If only. MySQL, PostgreSQL, Oracle, BerkeleyDB, or peach fuzz? The answer is obvious: pick the one your team is most capable and most comfortable with. Got it? Great! You've just solved the easiest problem you're ever going to have.

    Bah! Humbug.

  10. Re:being a paying customer... by Donny+Smith · · Score: 3, Insightful

    >MySQL has had replication for a long time already.

    Yeah, but how reliable (read: it sucks) is it?

    From TFA:
    "I believe it will change how MySQL is perceived in the market," said Axmark, who then added that he thought this release would make MySQL an option for at least ten times as many users as before."

    It says in the article that mySQL has a 40% share in the open source DB market. If they're gonna get 10x as many users, that'd be 400%, so I guess they plan to make further gains in the commercial market.
    If open source DBs have a 10% share (means shit, anyway), then mySQL plans to shoot from a 4% to a 40% market share. I just don't see that happening.

    About the market share: what does that mean - 40%? Of what? By number of copies in use, by data, by number of paying customers...?

  11. Fixing 10 years of criticism, 10 years too late by Osty · · Score: 5, Insightful

    In the ensuing 10 years, they've thoroughly corrupted the minds of young programmers and DBAs by making them think it's okay to sacrifice data integrity for the illusion of speed ("illusion", because mysql chokes when you get into complex data sets or queries; the vaunted speed of mysql only applies when you're working with a data set so simple you could represent it with flat files or xml without any difficulty). That it's okay to work around the shortcomings of a RDBMS in your application code (no, I am not going to implement transactions, referential integrity, or subqueries in my application code. That's just stupid). That you don't need views or sub-selects or triggers or stored procedures. That adding those features actually slows down your RDBMS (well, yeah, if you implement them poorly).

    While it's nice to see that they'll finally support most of the features of a proper RDBMS, it's too little too late. Even if they ship tomorrow it'll be years before this new version is ubiquitous (how many ISPs and hosting providers are still running an ancient 3.x version of MySQL?). The best way for them to have "fixed" those 10 years of criticism was never to have allowed the criticism in the first place -- by fully implementing an RDBMS, or at least acknowledging the benefits of the features you don't implement, like foreign keys, rather than spouting out crap about how adding those features will slow things down, and any "smart" programmer can do without them anyway. At least that way they could've avoided looking like hypocrites.

    "You don't need transactions. Transactions just slow things down. Look, we have table-level locks. Use those. You can ensure data integrity from your application by using table-level locks. Performance concerns on locking a full table to update a single row? What?" and then, "Would you look at that? Transactions! You can get them if you use this new table type. Of course, if you don't have that new table type and you try to use it, or you do have the new table type but you don't explicitly mark your tables as that new type, you're not going to get transactions. Oh, we won't fail, we'll just silently not open a transaction, and silently not rollback or commit when you ask us to."

    "Sub-selects? Sub-selects are slow. Why would you need sub-selects when you can do two queries, pull all of that data back to your application (because you don't need stored procedures either), and mimic the sub-select there?" and then, "Oo! Sub-selects! Pretty!"

    etc ...

    1. Re:Fixing 10 years of criticism, 10 years too late by quantum+bit · · Score: 4, Insightful

      i think your problem boils down to the fact you want the DB to do everything when really it doesn't matter. the application is there and the DB NEEDS IT cause no user sits down and writes SQL statements. if you were a competent programmer, doing "DB" things in your "application" wouldn't be stupid, it'd be easy, cause you'd know your data structures and your sorting algorithms like any CS grad.

      It's not that simple in the real world. Think about things like concurrency. If you have 200 clients running your app at the same time and 10 of them are trying to update a complex set of related tables, how do they avoid stepping on each others toes? Are you going to have your client apps communicate with each other and coordinate the inserts? Or just lock all the tables and kill performance? How do you ensure that everyone who is reading those tables sees a consistent data set?

      Or you could let the DB server do it, since it knows both the data model and the state of all the clients. Things like transactions keep clients from seeing unfinished inserts (and PostgreSQL and Oracle have MVCC to make this very efficient).

      Sure, for websites and blogs it doesn't really make a difference. Every once in a while you'll see some odd data appearing on the page but if you refresh it will be gone. MySQL has historically been very good at running simple things like this.

      Anything more important than that needs real data integrity at the database level. Application level checks can't *guarantee* the state of the database when more than 1 user is connected, no matter how careful they are.

  12. Re:being a paying customer... by fitten · · Score: 3, Insightful

    Yeah... a lot of folks use screwdrivers as chisels, wrenches as hammers, knives as screwdrivers, and pliars for wrenches, too. It doesn't make a screwdriver a chisel, a wrench a hammer, a knife a screwdriver, or pliars a wrench.

  13. So? by DogDude · · Score: 3, Insightful

    Sure it's not ACID, but it does well enough for most purposes

    Also works well enough for "most purposes": Flat files, MS Access, etc. That doesn't mean I'm going to build any kind of important app around them.

    --
    I don't respond to AC's.
  14. Re:being a paying customer... by Anthony+Boyd · · Score: 5, Insightful
    I'm hoping that the new MySQL won't sacrifice speed for all these features.

    Agreed. I don't think other database vendors understand the importance of speed to a Web Developer. We have to go over a network layer, with the requisite delays factored in. We use a client-server model, and cannot rely on the client CPU, like a traditional software product. And even a crappy Web site can find itself loaded down with a large audience. So we have to squeeze out milliseconds anywhere we can get them. A fast database and optimized code, that's pretty much what we can control.

    I mentioned this story once before on Slashdot, but it's relevant, so here it is. Borland had a product called Intrabuilder. It had a poor-man's version of Live Script on the backend, with a built-in database -- so back in 1997 you could do some very PHP-like stuff with the system. It was promising. But as a Web guy there, I was tasked with using it on the borland.com site. And it was giving me huge lag -- 1 or 2 seconds per simultaneous user. So with 5 people testing my app, each page took 10 seconds to display. I told this to the Intrabuilder team. Response? "That is an acceptable delay. It's how databases work." For all I knew, they were right. Maybe databases did work slowly like that back then. I was young & new to that stuff. But I knew that I didn't work that way and I didn't want my site to work that way either. Borland eventually abandoned the product, because the developers didn't see the shift in the market: Web Developers need speed. It's not like an ATM transaction, where I'll wait 15 seconds to get my money. MySQL needs to keep its speed, especially under load. And other database teams would be wise to take note.

  15. Re:What about foreign keys? by LurkerXXX · · Score: 5, Insightful
    Yea, they have foreign keys! WhooHoo! Unfortunately, they didn't bother implementing them correctly.

    The same way that MySQL has the constraints feature on columns. But it also isn't implemented correctly. If you insert out-of-bounds data, MySQL silently changes it to a number that it likes. Features implemented half-assed like that aren't really good features.

    If they implement views, triggers, and stored procedures in the same crappy way, MySQL is still going to be a crappy DBMS. It will have lots of broken features which will still make it an unsafe place to store data that you care about.

    As far as a reference for just some of the problems with their foreign key implementation, and as pointed out elsewhere in the thread, and found here...: http://sql-info.de/mysql/referential-integrity.htm l%233_5

    3. Foreign Keys and Referential Integrity Foreign keys are an essential part of any relational database. In MySQL's foreign key support has been added on through the InnoDB extension and is continually being improved. However some aspects of the foreign key implementation, especially in combination with other areas of functionality, may cause unexpected problems.

    3.1. ALTER TABLE ... SET NOT NULL If a NOT NULL constraint is applied to a column, MySQL will set any rows containing NULL in that column to 0 (in integer or numeric columns) or '' ( empty string, in character columns). No warning is given.

    In certain circumstances - particularly if the column contains character data - this may be quite practical, saving you an entire UPDATE tbl SET col = '' WHERE col IS NULL.

    But - imagine the column is an integer foreign key. And the column it references does not contain a zero. Hmmm...

    mysql> CREATE TABLE exmpl5 (
    id INT NOT NULL,
    val TEXT,
    UNIQUE (id) ) TYPE=InnoDB;
    Query OK, 0 rows affected (0.07 sec)

    mysql> CREATE TABLE exmpl6 (
    id INT,
    blah TEXT,
    INDEX(id),
    CONSTRAINT id_fkey FOREIGN KEY (id) REFERENCES exmpl5(id) ON DELETE NO ACTION ) TYPE=InnoDB;
    Query OK, 0 rows affected (0.04 sec)

    INSERT INTO exmpl5 VALUES(1, 'test');
    INSERT INTO exmpl6 VALUES(1, 'foo');
    INSERT INTO exmpl6 VALUES(NULL, 'bar');
    INSERT INTO exmpl6 VALUES(0, 'oops'); ERROR 1216: Cannot add a child row: a foreign key constraint fails

    SELECT * FROM exmpl6;
    | id | blah |
    | 1 | foo |
    | NULL | bar |
    2 rows in set (0.00 sec)

    So far so good - this proves the foreign key constraint is being taken seriously. Now the fun starts:

    ALTER TABLE exmpl6 CHANGE id id INT NOT NULL
    Query OK, 2 rows affected (0.12 sec)
    Records: 2 Duplicates: 0 Warnings: 1

    INSERT INTO exmpl6 VALUES(NULL, 'bar');
    ERROR 1048: Column 'id' cannot be null

    INSERT INTO exmpl6 VALUES(0, 'oops');
    ERROR 1216: Cannot add a child row: a foreign key constraint fails

    This is perfectly normal behaviour for a well-adjusted database. Now let's have another look at what the table contains:

    select * from exmpl6;

    | id | blah |
    | 1 | foo |
    | 0 | bar |
    2 rows in set (0.00 sec)

    I don't recall successfully inserting the zero in that second row - do you? Perhaps I secretly inserted a row into exmpl5 with 'id' set to 0?

    SELECT * FROM exmpl6 e6 LEFT JOIN exmpl5 e5 ON e5.id=e6.id;

    | id | blah | id | val |
    | 1 | foo | 1 | test |
    | 0 | bar | NULL | NULL |

    Err, no. All I can think of is that the foreign key was arrested as a potential terrorist suspect while I was seeing what other databases did given the same set of queries.

    (Note: MySQL 4.1.7 raises a warning after the ALTER TABLE statement above with the cryptic message Data truncated for column 'id' at row 2.)

  16. Re:being a paying customer... by trulymadlydeeply · · Score: 4, Insightful

    You're either a fool or a troll. I've develop for Oracle and MySQL. MySQL is faster by magnitudes. Even something like say, logging in, takes much longer on Oracle than in MySQL. In MySQL you feel like you're interacting with something at about the speed of the unix shell. In Oracle you feel like you are sending telegraphs off to a server that cranks away and responds to you after a while. Data integrity is not the only Oracle slowdown. Things like character set conversion make everything bog down. As far as "code overhead", modern development doesn't use much in the way of database constraints. They're nice from an ideal-world point of view, but it's awkard to try to insert a row and catch a constraint violation coming from way down deep in your database access code and few people do it. A little experiment: Try building a table in Oracle with the absolute loosest of constraints. All columns can be varchar2(100) with no primary or foreign keys and no check constraints. To be fair, I wouldn't use any exotic options like PARALLEL or NOLOGGING, but do whatever you will. Load it up with 10M rows and check your watch..... Do the same in MySQL and check your watch.... On second thought, you probably don't have access to either of these pieces of software.

  17. Re:being a paying customer... by Tassach · · Score: 5, Insightful
    It's faster than everything else because it doesn't have all the data integrity features that a RDBMS does
    Because after all, who really cares about data integrity?

    So what if the accounting system is off by $12,000,000? It's fast.

    Who cares if the customers actually get the products they ordered? It's fast.

    Who cares if we bill our customers for the right amount? It's fast.

    However, I stick everything into the application layer, so MySQL lacking these features doesn't bother me a bit.
    Yes, because it's so much more professional and a more efficient use of your time and employer's money to hack together a half-assed system rather than learning how to use a tested and proven one that someone else wrote.
    Scheduled DB backups and logging in the application layer keeps me from needing any transaction or rollback features.
    This statement just demonstrates the fact that you have no clue what transactions are for, or how and when to use them.
    --
    Why is it that the proponents of "one nation under God" are so eager to get rid of "liberty and justice for all"?
  18. foreign keys? try write-ahead logging by js7a · · Score: 5, Insightful

    write-ahead logging is why I use and advocate PostgreSQL. Witness the recent power failure problems at Livejournal in which WAL recovery would probably have cut downtime to a few hours instead of days.

  19. Opinions... by danheskett · · Score: 4, Insightful
    I worked with a group of professionals to port an COM+/MSSQL project to PHP/MySQL3.x platform.

    A 150GB database is very lower mid-range for a real-world database. Even with very "highly optimized" replacements of stored procedures and well-designed queries to replace views, and every tweak we could find or think of, they could never match the performance the client was used to on the old platform, even with more powerful hardware. After months of tweaking, the project failed, and I had to eat a lot of billable hours. The database choked down with any significant INSERT or UPDATE activity. In testing and demos, it was great - fast and zippy. When we threw the switch for a simulation of a real days work logged from the live system, the world nearly ended -- a 24 hr day of work for the live system took at our best 28 hours. For example, we had problems with queries that should require only indexed fields scanning an entire table for any given query. These are the problems you may never notice if you just run a small website from MySQL, but will hurt you when you have a table with 100M records in it.

    I hope and pray that 5.x allows me to port this application. I'd love to get the whole thing end to end on a free platform. (Postgres wouldn't fly with the customer at the time because of vague issues with not knowing the product, not wanting to gamble on another OSS project, etc).

    Everything about getting this app to MySQL was a nightmare. It was a complete non-stop cluster.. well.. you can imagine. By the time the project was called off I had devoted my most skilled programmer to looking for bottlenecks in and hacking MySQL code.

    We revisited the effort when the 4.x series hit its stride, but were afraid of the chance of failure again. We noticed that hard limits had been raised, and that the client lib was solidly performing, but, well, we never got things to that level where it beat what was already in place.

    Right now the database stands at 550GB or so (the server was upgraded to SQL2000 a while back [without incident, I may add]). If had of stuck with MySQL the first time through... I shudder to think where things would be 2+ years later. Failure, in this case, probably saved a lot of trouble.

    So, to the educated masses: can anyone speculate about this releases capabilities? The list of requirements would be:

    550GB, projected to be 1TB by 2007?

    2500 tables

    Full-text searching in approximately 1500 tables

    Queries that routinely join 25-150 tables

    ~800 stored procedures

    ~1500 views

    ~1000 triggers

    500-750 inserts/updates per second average, 20000 inserts per second peak, (approximately 40M new rows per day)

    1800-2500 queries per second average, 15000 queries per second peak

    Is MySQL 5.x the answer to my prayers? Or just a cruel reminder of why MS software costs what it does?

  20. Re:being a paying customer... by jusdisgi · · Score: 4, Insightful

    It's faster than everything else because it doesn't have all the data integrity features that a RDBMS does.

    I stick everything into the application layer, so MySQL lacking these features doesn't bother me a bit.

    So, you use the database because its lack of features makes it faster. But then you reinvent the wheel by writing those features into the application. Surely you realize how likely it is that you are wasting all that speed and more in the application layer trying to do a bunch of stuff that your database is supposed to handle for you. Unless you really think you are so superior to the coders at Postgres that you keep an advantage (good luck), you are wasting your time and adding foolish complexity to your apps for no reason.

    --
    Given a choice between free speech and free beer, most people will take the beer.
  21. Re:being a paying customer... by Stone316 · · Score: 4, Insightful
    I guess the point is, your doing extra work on behalf of the database that other RDBMS's provide. Its a complete and utter waste of your time to do transaction logging at the application level.. Its not like you will have to pay for Oracle or DB2.... Other OSS RDBM's provide you with that functionality.

    I've been a DBA for 8 years and i've seen countless developers spend days, weeks programming features that are already in the database. I thought developers loved to reuse code but I guess some like to do everything from scratch by themselves.

    I dunno, maybe if you had real dba's to tune the DB rather relying on developers supporting it, maybe you would see the same performance out of the 'slower' RDBMS like oracle, DB2, postgresql.

    Personally I'd rather rely on transaction logging, integrity being handled by the database.. Why? Because depending on the RDBMS they've been there a long time and pretty stable. Not to slight your skills but your time is probably better off spent on other parts of your code rather than somethings thats been tried, tested and true.

    --
    "Thanks to the remote control I have the attention span of a gerbil."
  22. Re:Come on stop whining! MySQL is SUPER! by LurkerXXX · · Score: 5, Insightful
    First: Transaction isolation and innodb can NOT solve these integrity problems.

    The integrity problems are specifically because of poor implementation of foreign key and other constraints. Read up at http://sql-info.de or a million other sites on the net. There are fundamental problems in their implementation. It doesn't matter if you are using transaction isolation or innodb tables, MySQL silently changes data in many many circumstances. This is bad.

    My 'users' aren't touching the database design. The database developers are. Multiple developers. When one makes a change and goes off shift, the next guy working on the table should immediately know if something changes made by the previous developer have invalidated some new data/scheme he's implementing. A database should never silently accept errors. It should always flag someone and refuse to make (or appear to make) a bad change.

    I don't know about your background, but a lot of MySQL users haven't a clue how a real database should be designed or what real data integrity is. I'm not bitching about MySQL not having features, I'm bitching about it's shoddy implementation of the features it already has. Foreign keys (in innodb) do not work right! Constraints do not work right! Many other basic features that MySQL claims to have do not work right!

    I'll say it again: A database should protect your data. It should not silently change data it doesn't like, instead of aborting the transaction and throwing proper error message.

    Postgres is also available for free. And it's designers appear to care about data integrity.